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A230806
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The smallest of 4 consecutive palindromic numbers that are all primes.
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2
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1878781, 11782828711, 13828882831, 33694849633, 36331813363, 76093839067, 93121812139, 1018278728101, 1101228221011, 1200528250021, 1237788877321, 1296978796921, 1318608068131, 1449108019441, 1477968697741, 1608678768061, 1713708073171, 1792308032971
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OFFSET
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1,1
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COMMENTS
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There cannot be 5 consecutive palindromic numbers that are all primes. The central digit of all numbers in the sequence will be 8.
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LINKS
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EXAMPLE
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1878781 is in the sequence because 1878781, 1879781, 1880881 and 1881881 are consecutive palindromic numbers that are all primes.
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MATHEMATICA
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a = {}; m = 0; Do[z = n*10^(IntegerLength[n] - 1) + FromDigits@Rest@Reverse@IntegerDigits[n]; If[PrimeQ[z], m = m + 1; If[m == 1, z1 = z]; If[m == 4, AppendTo[a, z1]], m = 0], {n, 1, 1000000000}]
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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